Automatic safety-clutch for windlasses and hoisting-machines.



J. B. PRUDEN. AUTOMATIC SAFETY CLUTCH FOR WINDLASSES AND HOISTING MACHINES.

APPLICATION IILBI) FEB. 26, 1908.

Patented Nov. 17, 1908.

a sums-$113M 1.

J. B. PRUDEN. AUTOMATIG SAFETY CLUTCH FOR WINDLASSES AND HOISTING MACHINES. APPLICATION FILED FEB. 26, 1908.

904.226. Patented Nov. 17, 1908.

3 SHEETS-SHEET 2.

J. B. PRUDEN.

AUTOMATIC SAFETY CLUTCH FOR WINDLASSES AND HOISTING MACHINES. APPLICATION FILED FEB. 28, 1908.

904,226. Patented Nov. 17, 1908.

3 SHEETS-SHEET 3. R 1 Q UNITED STATES PATENT OFFICE.

J'ESTER BRUFF PRUDEN, OF THOMPSON FALLS, MONTANA.

Specification of Letters Patent.

Patented Nov. 17, 1908.

Application filed February 26, 1908. Serial No. 417,959.

To all whom it may concern.-

Be it known that I, JEs'rEn BRUFF PRUDEN, a citizen of the United States, residing at Thompson Falls, in the county of Sanders, State of Montana, have invented a new and useful Automatic Safety-Clutch for Vindlasses and Hoisting-Machines, of which the following is specification.

The object of the invention is to provide a device by which windlasses or hoisting machines (whether the load is ascending or descending) will be automatically stopped in case of accident-thus should the cranksman or engineer lose control while hoisting or lowering a heavy load and. the Windlass start to run backthe safety clutch automatically and instantly stops the Windlass at a quarter turn which on a Windlass drum of ordinary size would allow the load to drop only about four of five inches.

The nature of the invention is as follows: The drum of the windlass or hoist has four safety bolts (intended to be about one inch in diameter by about sixteen inches long) which bolts run through the drum and are prevented from falling entirely through by a head on either end. On one end of the drum these bolts are set at right angles with each otheron the other end of the drum the two safety bolts are set at right angles with each other but at 45 degrees to the pins on the other end of the drum. The safety bar on which these bolts catch or clutch to stop the Windlass, in case of accident, is a steel or iron bar which is held in place over the drum, running parallel with the drum, and under which bar these pins pass when Windlass is being turned at ordinary speed that is to say that when the Windlass is being turned at a speed of say from thirty to fifty revolutions per minute, or at a less speed, these pins keep dropping through the drum by their own weight as the drum revolves. But should the speed of the Windlass be suddenly increased, whether in hoisting or' lowering, by reason of any accident whereby control is lost-these safety pins are instantly thrown out to their full length by centrifugal force and catch on the safety bar thus stopping the windlass before it can make more than a quarter of a turn after control has been lost. This safety bar can quickly and easily be thrown out of place by a lever within easy reach of the operator thus allowingthe Windlass to be operated at greater speed as an ordinary Windlass in case it is desired to lower empty buckets or light loads rapidly. The safety device when in operation will allow the drum to revolve at a speed of fifty revolutions per minute which is more than double the speed of ordinary hoisting.

The object of this safety clutch is to insure absolute safety to the men at the bottom of the shaft when heavy loads are being hoisted and lowered and also to insure safety to occupants of buckets, cages and tram cars when the same are being either raised or lowered by means of a cable winding or unwinding on a drum. I attain this object by means of a mechanism illustrated in the three accompanying drawings, in which Figure 1 is an end view of the machine assembled and ready for operation (except that no crank is shown on shaft or gudgeon pin P as I was obliged to omit this in the drawing as it obscured the view of more important parts). Fig. 2 shows side view of machine assembled and ready for operation. Fig. 3 is a top view of machine assembled and ready for operation.

Similar letters refer to similar throughout the several views.

Dctailerl Dcscm'qnfioa In the drawings, A. indicates the frame which is constructed with legs to support the machine and is so constructed as to make a U shaped slot or receptacle into which safety bar D fits when safety appliance is on. The said safety bar D when thus in place rests or bears against frame A on either side at right angles so that when safety bolts T are thrown out and catch on safety bar D and bear against said bar D at right angles, said bar D then bears against one side or the other of said slot or receptacle in frame A. The same result is obtained whether drum S is revolving forward as in hoisting or backward as in lowering.

B indicates a brace for frame A.

C indicates a bolt running through frame A to hold safety bar D at a proper height above flange R while in operation.

D indicates the safety bar on which safety bolts T catch or clutch to stop the Windlass in case of accident.

D is a steel or iron bar which is held in place over drum S by resting on bolts C in the slot in frame A, said bar D running parallel with said drum S and resting in a horizontal position in said slot in frame A.

parts lVhen the windlass is revolving at ordinary speed so that drum S is revolving either way at a speed of from twentyfive to fifty revolutions per minute, bolts T drop through drum S, of their own weight and pass under clear of safety bar D. When the speed of drum S is suddenly increased safety bolts T are thrown out, by centrifugal force, to their full length and catch on safety bar D, thus instantly stopping drum S before it can make more than a quarter turn after the speed has been thus suddenly increased, Safety bar D is thrown out of position by a handle G thus allowing drum S to revolve as rapidly as desired and when drum S is thus rapidly revolving safety bolts T even though they are thrown out and held out to their full length will pass under clear of bar M which bar M is a part of frame A.

E indicates rods connecting. lever F and bar D.

F indicates a lever provided with a curved arm for lifting safety bar D out of place in the slot in frame A.

G indicates the handle on lever F.

H indicates bolts on bar M supporting lever F.

I indicates a pin connecting bolt E and arm F.

J indicates an enlarged part of drum S through which safety bolts T work.

J indicates an enlarged part of drum between flanges R and Q, and is intended for a common rope brake to work on.

K indicates a bolt running through frame A to hold gudgeon pin P in position.

M indicates bars supporting and bracing frame A.

0 indicates bolts fastening frame A and bars M together at each end.

P indicates the gudgeon pin or axle on which the handle or crank is attached.

Q indicates flanges protecting the rope brake from frame A.

R indicates flanges protecting safety bolts T from the hoisting cable winding on drum S and from the brake rope winding on J.

S indicates the drum proper.

T indicates the four safety bolts running through drum S. As said drum S revolves bolts T fall through holes in drum S by their own weight and are prevented from falling entirely through by a head on each end. Said bolts T are set in pairs of two, well out toward the two ends of drum S. On one end of drum S these bolts are set at right angles with each other while on the other end of drum S they are also set at right angles with each other but at degrees to the first mentioned pair. Bolts T are so set in drum S as to allow only about a quarter of a turn of drum S before bolts T catch on bar D as hereinbefore described.

I claim,

The combination in an automatic safety clutch for windlasses and hoisting machines, of the frame A the drum S the safety bolts T which work in and through said drum S the safety bar D against which said bolts T are adapted to catch or clutch, and the handle G on said safety bar D for lifting same; the frame A being provided with a U shaped slot or receptacle in which said safety bar D rests when in place, all substantially as set forth.

JESTER BRUFF PRUDEN.

lVitnesses DAVID J. Horn, TVILLIAM ALLEN BARTO. 

